Antenna



FIG. 1 is an environmental front elevation view of an antenna, showing our new design;

FIG. 2 is a side plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is rear elevation view thereof;

FIG. 5 is a top perspective view thereof;

FIG. 6 is a front elevation view of the antenna;

FIG. 7 is a side elevation view thereof; and,

FIG. 8 is a top plan view thereof.

The broken lines illustrate environment and form no part of the claimed design. 

CLAIM The ornamental design for an antenna, as shown and described. 